The construction and installation of prefabricated panels in the roof and sidewall areas of building construction has been the object of much design effort, and a number of different designs have been commercially successful to varying degrees. The present invention relates to structures of the type wherein panels are preformed of sheet metal or other strong sheet material and are provided with longitudinal ribbing which forms a part of the retaining means for securing the panels to blind fastening clips attached to the building frame structure.
Building panels so designed as to be held from beneath by fastening means which require no apertures in the panels and which provide a leakproof structure under the severe conditions encountered in roofing applications have been designed with standing seams which are deformed during installation of the panels to interlock the edges of adjacent panels and simultaneously interlock the seamed areas with underlying fastener clips preattached to the framing elements of the building. Although a number of such systems achieve satisfactory performance, many of them require that each workman be equipped with a heavy and expensive seam crimping machine which he must often manipulate on a roof under difficult conditions. The seaming machines are also typically slow, and involve dealing with an electrical supply cord. The design of the preformed seamable contours in the panels also frequently prevents efficient nesting of the panels for shipment. It will be appreciated that these disadvantageous factors have the net effect of adding to the cost of the finished structure.
Where seaming machines are used they also usually leave marks on the seams, which is of course undesirable when the panels are to be installed in areas which are readily visible, as in wall construction.
Preformed seam portions have also been used which are designed to be pounded together and onto underlying holding clips in the field by means of a rubber mallet. Due to the small size of such pounded seams, however it is difficult to insure that they are fully interlocked, leakproof and capable of withstanding the high lift off forces created by winds. Also, during installation almost all known panel designs present locating or positioning problems in that a significant amount of time may be required to make sure that the anchoring means are properly spaced and/or that all through fasteners in fact pass through the supporting structure. Many prior standing seam designs also require a separate cap element. The present invention eliminates such problems and requires no cap.
With the foregoing in mind, it is the overall object of the present invention to provide an improved panel construction of the general type disclosed in the aforementioned prior application, which is so designed that the installer can secure the panels to the principal attaching means and thereby to the frame structure of the building merely by pressing the panels into place with his foot, but which is inherently stronger and more quickly installable than the construction disclosed in said prior application.